Angelica gigas (Dang Gui or Giant Angelica, Purple Parsnip, Korean Angelica) is a monocarpic biennial or short lived perennial plant from China, Japan and Korea. It inhabits forests, grasslands and banks of streams. The roots are used in traditional Chinese medicine.

Research in 2007 has isolated a chemical from the root of the plant, a coumarinderivative called decursin, that may have anti-androgenic properties in vitro.[2] In 2013, the main substance decursin, decursinol angelate (its isomer), JH714 (the ether form) and epoxide decursin (the epoxide form) were analyzed in vitro and in vivo. CYP isoforms were inhibited more than 50%. There was good blood brain barrier permeability in rats after oral administration of all but epoxide. Pharmacokinetic studies after oral and intravenous administration of 10 mg/kg showed that after 8 hours all test compounds stayed in the gastrointestinal tract at more than 1.5% of the dose and less than 0.5% was excreted in urine.[3]